1. Field of the Invention
The present invention generally relates to a motor controlling apparatus. More particularly, the present invention relates to an apparatus and method for controlling a motor by stabilizing and controlling an inverter that provides power to a motor to mitigate a decline in the efficiency of the inverter.
2. Background Information
In a typical device for controlling an alternating-current motor, a voltage being applied to the motor is controlled using an inverter. Also, the control device selects between a first control line and a second control line according to the active area of the alternating-current motor. Accordingly, the controller generates a current command that corresponds to the torque command value associated with the selected control line. That is, as described in Japanese Laid-Open Patent Application No. 2010-130726, the first control line sets a torque current command corresponding to the torque command value according to the phase of the current in which the torque of the alternating-current motor reaches a maximum with respect to the amplitude of the current. On the other hand, the second control line sets a torque current command corresponding to the torque command value according to the phase of the current in which the amplitude of the current corresponding to the torque is higher than in the first control line.